With Merlin gravely ill from the serket's poison, Morgana and Morgause continue
with their evil plan. They have mentally incapacitated Uther and convinced his enemy,
Cenred, to invade Camelot. The fate of the kingdom now rests on Arthur's shoulders.
The Prince and his men resist the invaders, but Cenred's soldiers are not the only
threat they face. Can Merlin stop Morgana in time to save Arthur from the enemy within?

Starring: Colin Morgan (Merlin), Angel Coulby (Gwen), Bradley James (Arthur Pendragon),
Katie McGrath (Morgana), Anthony Head (Uther Pendragon), Richard Wilson (Gaius),
John Hurt (Voice of the Great Dragon)

Guest Starring: Emilia Fox (Morgause), Tom Ellis (Cenred), Rupert Young (Sir Leon),
Alice Patten (Ygraine), Jake Phillips (Ghost Boy)

Creatures: The Great Dragon, Skeleton Warriors

Written by Julian Jones
Directed by Jeremy Webb

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